/******************************************************************************
 * @file     fast_math_functions.h
 * @brief    Public header file for CMSIS DSP Library
 * @version  V1.10.0
 * @date     08 July 2021
 * Target Processor: Cortex-M and Cortex-A cores
 ******************************************************************************/
/*
 * Copyright (c) 2010-2020 Arm Limited or its affiliates. All rights reserved.
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the License); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _FAST_MATH_FUNCTIONS_H_
#define _FAST_MATH_FUNCTIONS_H_

#include "arm_math_types.h"
#include "arm_math_memory.h"

#include "dsp/none.h"
#include "dsp/utils.h"

#include "dsp/basic_math_functions.h"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @brief Macros required for SINE and COSINE Fast math approximations
 */

#define FAST_MATH_TABLE_SIZE 512
#define FAST_MATH_Q31_SHIFT  (32 - 10)
#define FAST_MATH_Q15_SHIFT  (16 - 10)

#ifndef PI
#define PI 3.14159265358979f
#endif

/**
 * @defgroup groupFastMath Fast Math Functions
 * This set of functions provides a fast approximation to sine, cosine, and square root.
 * As compared to most of the other functions in the CMSIS math library, the fast math functions
 * operate on individual values and not arrays.
 * There are separate functions for Q15, Q31, and floating-point data.
 *
 */

/**
 * @brief  Fast approximation to the trigonometric sine function for floating-point data.
 * @param[in] x  input value in radians.
 * @return  sin(x).
 */
float32_t arm_sin_f32(
    float32_t x);

/**
 * @brief  Fast approximation to the trigonometric sine function for Q31 data.
 * @param[in] x  Scaled input value in radians.
 * @return  sin(x).
 */
q31_t arm_sin_q31(
    q31_t x);

/**
 * @brief  Fast approximation to the trigonometric sine function for Q15 data.
 * @param[in] x  Scaled input value in radians.
 * @return  sin(x).
 */
q15_t arm_sin_q15(
    q15_t x);

/**
 * @brief  Fast approximation to the trigonometric cosine function for floating-point data.
 * @param[in] x  input value in radians.
 * @return  cos(x).
 */
float32_t arm_cos_f32(
    float32_t x);

/**
 * @brief Fast approximation to the trigonometric cosine function for Q31 data.
 * @param[in] x  Scaled input value in radians.
 * @return  cos(x).
 */
q31_t arm_cos_q31(
    q31_t x);

/**
 * @brief  Fast approximation to the trigonometric cosine function for Q15 data.
 * @param[in] x  Scaled input value in radians.
 * @return  cos(x).
 */
q15_t arm_cos_q15(
    q15_t x);

/**
  @brief         Floating-point vector of log values.
  @param[in]     pSrc       points to the input vector
  @param[out]    pDst       points to the output vector
  @param[in]     blockSize  number of samples in each vector
  @return        none
 */
void arm_vlog_f32(
    const float32_t *pSrc,
    float32_t *pDst,
    uint32_t blockSize);

/**
  @brief         Floating-point vector of log values.
  @param[in]     pSrc       points to the input vector
  @param[out]    pDst       points to the output vector
  @param[in]     blockSize  number of samples in each vector
  @return        none
 */
void arm_vlog_f64(
    const float64_t *pSrc,
    float64_t *pDst,
    uint32_t blockSize);

/**
 * @brief  q31 vector of log values.
 * @param[in]     pSrc       points to the input vector in q31
 * @param[out]    pDst       points to the output vector in q5.26
 * @param[in]     blockSize  number of samples in each vector
 * @return        none
 */
void arm_vlog_q31(const q31_t *pSrc,
                  q31_t *pDst,
                  uint32_t blockSize);

/**
 * @brief  q15 vector of log values.
 * @param[in]     pSrc       points to the input vector in q15
 * @param[out]    pDst       points to the output vector in q4.11
 * @param[in]     blockSize  number of samples in each vector
 * @return        none
 */
void arm_vlog_q15(const q15_t *pSrc,
                  q15_t *pDst,
                  uint32_t blockSize);

/**
  @brief         Floating-point vector of exp values.
  @param[in]     pSrc       points to the input vector
  @param[out]    pDst       points to the output vector
  @param[in]     blockSize  number of samples in each vector
  @return        none
 */
void arm_vexp_f32(
    const float32_t *pSrc,
    float32_t *pDst,
    uint32_t blockSize);

/**
  @brief         Floating-point vector of exp values.
  @param[in]     pSrc       points to the input vector
  @param[out]    pDst       points to the output vector
  @param[in]     blockSize  number of samples in each vector
  @return        none
 */
void arm_vexp_f64(
    const float64_t *pSrc,
    float64_t *pDst,
    uint32_t blockSize);

/**
 * @defgroup SQRT Square Root
 *
 * Computes the square root of a number.
 * There are separate functions for Q15, Q31, and floating-point data types.
 * The square root function is computed using the Newton-Raphson algorithm.
 * This is an iterative algorithm of the form:
 * <pre>
 *      x1 = x0 - f(x0)/f'(x0)
 * </pre>
 * where <code>x1</code> is the current estimate,
 * <code>x0</code> is the previous estimate, and
 * <code>f'(x0)</code> is the derivative of <code>f()</code> evaluated at <code>x0</code>.
 * For the square root function, the algorithm reduces to:
 * <pre>
 *     x0 = in/2                         [initial guess]
 *     x1 = 1/2 * ( x0 + in / x0)        [each iteration]
 * </pre>
 */

/**
 * @addtogroup SQRT
 * @{
 */

/**
  @brief         Floating-point square root function.
  @param[in]     in    input value
  @param[out]    pOut  square root of input value
  @return        execution status
                   - \ref ARM_MATH_SUCCESS        : input value is positive
                   - \ref ARM_MATH_ARGUMENT_ERROR : input value is negative; *pOut is set to 0
 */
__STATIC_FORCEINLINE arm_status arm_sqrt_f32(
    const float32_t in,
    float32_t *pOut)
{
    if (in >= 0.0f) {
#if defined(__CC_ARM)
#if defined __TARGET_FPU_VFP
        *pOut = __sqrtf(in);
#else
        *pOut = sqrtf(in);
#endif

#elif defined(__ICCARM__)
#if defined __ARMVFP__
        __ASM("VSQRT.F32 %0,%1" : "=t"(*pOut) : "t"(in));
#else
        *pOut = sqrtf(in);
#endif

#else
        *pOut = sqrtf(in);
#endif

        return (ARM_MATH_SUCCESS);
    } else {
        *pOut = 0.0f;
        return (ARM_MATH_ARGUMENT_ERROR);
    }
}

/**
  @brief         Q31 square root function.
  @param[in]     in    input value.  The range of the input value is [0 +1) or 0x00000000 to 0x7FFFFFFF
  @param[out]    pOut  points to square root of input value
  @return        execution status
                   - \ref ARM_MATH_SUCCESS        : input value is positive
                   - \ref ARM_MATH_ARGUMENT_ERROR : input value is negative; *pOut is set to 0
 */
arm_status arm_sqrt_q31(
    q31_t in,
    q31_t *pOut);

/**
  @brief         Q15 square root function.
  @param[in]     in    input value.  The range of the input value is [0 +1) or 0x0000 to 0x7FFF
  @param[out]    pOut  points to square root of input value
  @return        execution status
                   - \ref ARM_MATH_SUCCESS        : input value is positive
                   - \ref ARM_MATH_ARGUMENT_ERROR : input value is negative; *pOut is set to 0
 */
arm_status arm_sqrt_q15(
    q15_t in,
    q15_t *pOut);

/**
 * @} end of SQRT group
 */

/**
@brief         Fixed point division
@param[in]     numerator    Numerator
@param[in]     denominator  Denominator
@param[out]    quotient     Quotient value normalized between -1.0 and 1.0
@param[out]    shift        Shift left value to get the unnormalized quotient
@return        error status

When dividing by 0, an error ARM_MATH_NANINF is returned. And the quotient is forced
to the saturated negative or positive value.
*/

arm_status arm_divide_q15(q15_t numerator,
                          q15_t denominator,
                          q15_t *quotient,
                          int16_t *shift);

/**
@brief         Fixed point division
@param[in]     numerator    Numerator
@param[in]     denominator  Denominator
@param[out]    quotient     Quotient value normalized between -1.0 and 1.0
@param[out]    shift        Shift left value to get the unnormalized quotient
@return        error status

When dividing by 0, an error ARM_MATH_NANINF is returned. And the quotient is forced
to the saturated negative or positive value.
*/

arm_status arm_divide_q31(q31_t numerator,
                          q31_t denominator,
                          q31_t *quotient,
                          int16_t *shift);

/**
   @brief  Arc tangent in radian of y/x using sign of x and y to determine right quadrant.
   @param[in]   y  y coordinate
   @param[in]   x  x coordinate
   @param[out]  result  Result
   @return  error status.
 */
arm_status arm_atan2_f32(float32_t y, float32_t x, float32_t *result);

/**
   @brief  Arc tangent in radian of y/x using sign of x and y to determine right quadrant.
   @param[in]   y  y coordinate
   @param[in]   x  x coordinate
   @param[out]  result  Result in Q2.29
   @return  error status.
 */
arm_status arm_atan2_q31(q31_t y, q31_t x, q31_t *result);

/**
   @brief  Arc tangent in radian of y/x using sign of x and y to determine right quadrant.
   @param[in]   y  y coordinate
   @param[in]   x  x coordinate
   @param[out]  result  Result in Q2.13
   @return  error status.
 */
arm_status arm_atan2_q15(q15_t y, q15_t x, q15_t *result);

#ifdef __cplusplus
}
#endif

#endif /* ifndef _FAST_MATH_FUNCTIONS_H_ */
